21473087328 has 864 divisors, whose sum is σ = 83894952960. Its totient is φ = 5132574720.

The previous prime is 21473087303. The next prime is 21473087387. The reversal of 21473087328 is 82378037412.

21473087328 is a `hidden beast` number, since 2 + 14 + 7 + 308 + 7 + 328 = 666.

It is a super-2 number, since 2×21473087328² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 208476525 + ... + 208476627.

It is an arithmetic number, because the mean of its divisors is an integer number (97100640).

Almost surely, 2^21473087328 is an apocalyptic number.

21473087328 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21473087328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41947476480).

21473087328 is an abundant number, since it is smaller than the sum of its proper divisors (62421865632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21473087328 is a wasteful number, since it uses less digits than its factorization.

21473087328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240 (or 222 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The spelling of 21473087328 in words is "twenty-one billion, four hundred seventy-three million, eighty-seven thousand, three hundred twenty-eight".